Solving fatal error:failed opening required anomalies

Solve fatal error:failed opening required error!
Error message:
Warning:require_once (Abc.class.php) [Function.require-once]: failed to open stream:no such file or directory in D:\myphp Www\print.php on line 3

Fatal error:require_once () [function.require]: Failed opening required ' Abc.class.php ' (include_path= '); C:\php6\pear ') in D:\myphpwww\Print.php on line 3

print.php file: Introducing Abc.class.php Files
Require_once ' Abc.class.php ';

Abc.class.php file:
Class abc{
Receive a number and print the pyramid
Public Function Printstar ($n) {

for ($i =1; $i <= $n; $i + +) {
Print Space first
for ($k =1; $k <= $n-$i; $k + +) {
echo "";
Print the number of asterisks
}
for ($j =1; $j <= ($i-1) *2+1; $j + +) {
echo "*";
}
Echo
";
}
}
}

?>



Online said (1) cannot find the file, is the path error, but the reference path is not wrong Ah,
(2) said to be a folder permissions problem, but the D disk folder all gave, modified.
Hope that the great God is not generous to enlighten you.
------Solution--------------------
But I don't see the print.php file in the map.
------Solution--------------------
Print.php and Abc.class.php to put the same record.
------Solution--------------------
Your name is wrong.
The Intercept is Abc.calss.php
And your include is the
Abc.class.php

